Elevated levels of nitrogen and E. coli bacteria were detected in Bozeman Creek. The creek is a popular waterway that runs right through the city and downtown.
The Water Quality District tested four different sites around Bozeman -- upstream of the city, near Bogert Park, near City Hall and downstream of Bozeman.
Tests completed last summer showed that both nitrogen and E. coli levels were above state water quality targets.
E. coli is a bacteria found in human and animal waste. It can find its way into streams from livestock and dog waste. It can make people sick. Nitrogen is a common ingredient in fertilizers.
NBC Montana looked into why nitrogen and E. coli levels are elevated and spoke with locals to find out their reactions on the latest developments.
At Bogert Park, people have easy access to the creek and often come to swim and play in its water.
"We've been coming here about once a week with the kids for a couple of weeks now," said Bozeman resident Carolyn Upchurch.
She brings the children she babysits to play at the park. She said she was surprised by the findings and is weighing whether to continue to letting the kids play in creek.
"In the summer time months, the E. coli bacteria is at an elevated level," said Gallatin Water Quality District Manager Tammy Swinney.
The Gallatin County Water Quality District is the department testing Bozeman Creek.
"That DEQ would prefer not to see, but that's what our information was gathering," said Swinney.
The Gallatin Water Quality District says that even though levels are elevated, it's still safe to play in the river as long as you practice good hygiene, which means washing your hands and not drinking the water.
Not everyone was surprised by the increased levels.
"It's not shocking for a creek that runs through the middle of town that your going to see that," said stay-at-home dad and Bozeman resident Tom Mazurek.
Mazurek comes to Bogert Park often and lets his kids play in the creek. He said he is paying attention to the issue, but isn't too concerned right now.
The county Water Quality District says people shouldn't be concerned, but can take steps to help bring down the levels.
"Its important to have those septic systems maintained and pumped on a regular basis and make sure that they are functioning properly so they don't leak," said Swinney.
They also say to pick up any pet waste.